Patent GB-478029-A (GB)
Title: Improvements in duplicating machines
IPC: B65H9/06
Filed: 1936-12-15
Abstract: 478,029. Duplicating-machines. BURGESS, A. F. (Ditto, Inc.) Dec. 15, 1936, No. 34420. [Classes 100 (i) and 100 (ii)] Hectograph - copying apparatus.- Sheets 93, Fig. 10, are fed to and stripped from a rotatable printing-drum, such as an arcuate drum 55, on which is mounted a gelatinecoated band 66, by three rollers 81 ... 83, the roller 81 co-operating with the roller 82, which is a platen roller, to feed the sheets, and with the roller 83 to deliver them. The rollers 82, 83 are mounted in bearings slidable in guides under the influence of spring-pressed plungers and are driven by friction from the roller 81, which is driven by gearing from the drum 55 and has a speed slightly greater than that of the drum. The leading edge of each printed sheet is directed to the rollers 81, 83 by fingers 61 fixed to a shaft 63 which is rocked by a stationary cam, a guard plate 126 preventing the sheets from falling below the roller 83. The sheets subsequently pass over spring guides 128 into a tray 129 in which they are held down by a pivoted rod 130. A feed-tray 131 and the tray 129 are hooked over rods 108, 33a respectively and are connected by arms so that the trays may be folded together for storage. Printing-surfaces.-A clip 67, Fig. 10, attached to one end of the band 66 is hooked over a flange on the drum, and a clip 68 at the other end is attached to a lug 69 on a shaft 70, which is rotatable to draw the band taut and is held in adjusted position by a ratchet 71 and pawl 72. Openings 77 in the drum prevent air pockets from forming under the band. Feeding sheets.-The sheets are fed by hand or automatically into a throat formed between a lower guide-plate 91, Fig. 10, pivotal about the shaft 108, and an upper plate 113 secured to the plate 91 which forms a margin stop and is periodically lowered by levers 117a rocked about a pivot -118 by a cam fixed to the drum 55. The plate 91 has forwardly-extending fingers 90 arranged opposite to peripheral grooves in the feed roller 81 and is normally pressed upwardly by springs 111 so as to prevent engagement of the rollers 81, 82. The sheetsupport 131 is provided with side guides 137, 138, Figs. 1 and 18, which are made of sheet metal folded to form vertical ribs and are adjustable laterally in slots 142...145. Plates 151, 152 welded to the guides 137, 138. and a rubber block 153 secured in a casing fixed to the underside of the sheet-support raise the centre of the pile of sheets and so facilitate separation of the top sheet. Sponge-rubber blocks 158, 159 are pressed against.the sides of the pile to align the sheets, each block being mounted in a holder 170 carried by a plate 160 having pins 162, 163 engaging slots 164, 165 whereby longitudinal movement of the plate 160 will move the block laterally. When automatic feed is required, a frame 195 is swung down from the broken line position, Fig. 10, so that a separator roller 203 rests on the sheets. The frame 195 is reciprocated by a rod 188 connected to a lever 179 oscillated by a cam 79, and the spindle of the roller 203 engages slots 205a so that during the movement of the frame to the left the roller is free to rotate and during the feeding stroke a bar 209 engages the roller and prevents rotation thereof. When the feed mechanism is moved into the inoperative, the lever 179 is moved away from the cam 79.